1. Field of the Invention
The present invention relates to a passage composite, and the use of a passage composite in an ink jet head and in a printer.
2. Description of the Related Art
Known ink jet heads for ejecting ink from nozzles to a sheet of paper each include a passage unit having a plurality of individual ink passages extending to nozzles arranged on the bottom surface of the ink jet head, and a reservoir unit that temporarily stores ink and supplies the ink to the passage unit.
In the known ink jet heads, the reservoir unit has a laminate structure including a passage block and three metal plates. The passage block is long in the main scanning direction and is made of a thermoplastic resin. Each metal plate has a rectangular planar surface that is long in the main scanning direction. The reservoir unit has an ink passage therein. The passage block has a loop projection and defines at least part of a passage opening closed by a film. The passage block has ribs projecting perpendicular to the first surface. Some of the ribs are connected to the outer surface of the loop projection.